Methods for initiating health behavior change have been studied extensively, but little empirical attention has been given to understanding factors that sustain long-term behavior changes. This application proposes to develop a model for long-term maintenance of behavior change by beginning to examine the basic parameters and processes of a behavioral treatment that has been extremely successful in initiating and sustaining periods of drug abstinence among drug dependent individuals. Contingency management (CM) procedures have been consistently effective in initiating drug abstinence in the majority of drug users and have sustained continuous abstinence for periods of up to 6 months. Despite the documented effectiveness of these interventions, the vast majority of CM interventions are kept in place for only 3 months. We propose to examine the effects of extending the duration of CM for drug abuse on long-term abstinence outcomes. We are not necessarily suggesting that the particular CM procedures we are proposing represent an immediately practical method of promoting long-term behavior change. We are suggesting that they provide a practical framework for beginning to investigate a behavioral model of maintaining drug abstinence. Following the tenets of basic behavioral research, we have outlined a model for long-term behavior maintenance that suggests that successful long-term behavior change does not focus on undoing old behaviors, but concentrates on developing new behaviors in a wide variety of new contexts, and provides enduring reinforcement for the new behaviors. This model predicts that interventions that promote long-term behavior change must provide a sufficient duration of treatment-contrived contingencies to develop new behaviors that are incompatible with drug use, and the new behaviors must have naturally-occurring sustaining contingencies. Research questions address issues of CM duration, the development of new behaviors incompatible with drug use, and the availability of natural maintaining contingencies of reinforcement.